1. Field of the Invention
The present invention relates to a fluid flow passage structure as well as a manufacturing method thereof. More specifically, the invention concerns a fluid flow passage structure and manufacturing method for forming a fluid flow passage between block members by means of wires, by sandwiching and gripping the wires between a plurality of metallic block members.
2. Description of the Related Art
In a solenoid manifold, an ejector apparatus or the like, it has been known conventionally to form fluid flow passages within a body having a cubic or rectangular parallelepiped shape formed from metal. Various methods have been adopted for providing the fluid flow passages therein.
For example, in Japanese Laid-Open Patent Publication No. 08-035506, a technical concept is disclosed whereby, after forming fluid flow passages by means of photoetching or press processing in a pair of body portions, a lid and a bottom, which are manufactured separately, are stacked and joined thereto. (See, paragraphs [0003] and [0007] of Japanese Laid-Open Patent Publication No. 08-035506.)
Japanese Laid-Open Patent Publication No. 11-125378 discloses a technical concept for manufacturing a fluid pressure manifold 1, in which a stacked body is formed by metal plates 2a, 2b and 2c, in which a plurality of holes 3a, 3b are provided in the upper surface metal plate 2a and the lower surface metal plate 2c, and wherein a plurality of fluid flow passages 4 are formed by laser illumination in the metal plate 2b, which is placed between the two metal plates 2a and 2c. (See, Japanese Laid-Open Patent Publication No. 11-125378, paragraph [0020].)
Japanese Laid-Open Patent Publication No. 2003-062671 discloses a manufacturing method for a manifold, in particular, wherein fluid flow passages 3 are formed by a grinding process in a pair of split base pieces 4, 5 that make up a base member 1. (See, Japanese Laid-Open Patent Publication No. 2003-062671, paragraph [0010].)
However, in conventional techniques like the foregoing, for example, when grooves are formed by means of photoetching as disclosed in Japanese Laid-Open Patent Publication No. 08-035506, multiple processes must be carried out including preparations for such processes, and considerable time is required until the grooves are fully formed. In the case of press processing, costs required for the mold become quite substantial. In the case of laser illumination as in Japanese Laid-Open Patent Publication No. 11-125378 as well, the apparatus therefor is large in scale and high manufacturing costs cannot be avoided.
Further, when grooves are formed as in Japanese Laid-Open Patent Publication No. 2003-062671, complex carving of the groove formations is necessary according to the grinding process, such that the manufacturing process becomes complicated, with considerably long manufacturing times, and ultimately, production efficiency is not improved.
Moreover, a drill generally has been used in the case of forming fluid flow passages. For example, as shown in FIG. 16, when a bent fluid flow passage 4 is formed inside of one metallic block member 1 by a first fluid flow passage 2 and a second fluid flow passage 3, the following type of process is required. First, a first flow passage 2 is cut by a non-illustrated drill in one side surface 1a of the block member 1. Next, a second flow passage 3 is cut by a drill from a second side surface 1b. In addition, a blind plug 5 is used for blocking a connecting portion between the first flow passage 2 and the second flow passage 3.
Stated otherwise, the process used in forming the bent fluid flow passage inside the block member 1 is complex, and the numbers of parts used, such as the blind plug, are increased. Notwithstanding, in cases where the fluid flow passages 2, 3 are narrow, for example, having diameters of 1 mm or less, the drill also becomes narrow in width, such that the drill axis is deflected during cutting and accurate formation of the flow passages is difficult. Even further, it may be impossible to form curved fluid flow passages inside the block member 1 by means of a drill.